ABSTRACT
INTRODUCTION Amorphous solids are an integral part of pharmaceutical research and development, and thus, an understanding of amorphous solids in relation to crystalline solids and liquids is essential. This is self-evident when a drug is intentionally made amorphous to increase bioavailability, or an amorphous polymer or excipient is purposely incorporated into a pharmaceutical product to provide elegance, and improve performance or stability. What may be less obvious is the potential for amorphous solids to be formed during processing of drugs and excipient into dosage forms, or for amorphous regions to exist in nominally crystalline materials. This requires an understanding of the how amorphous materials can be formed, the persistence of any amorphous solids during manufacturing, and the potential for subsequent physical or chemical change during storage.
